[PATCH 3/4] media: sunxi-cir: Factor out hardware initialization

[Samuel Holland]

In preparation for adding suspend/resume hooks, factor out the hardware
initialization from the driver probe/remove functions.

The timeout programmed during init is taken from the `struct rc_dev` so
it is maintained across an exit/init cycle.

This resolves some trivial issues with the probe function: throwing away
the error from clk_prepare_enable and using the wrong type for the
temporary register value.

Signed-off-by: Samuel Holland <samuel@xxxxxxxxxxxx>
---
 drivers/media/rc/sunxi-cir.c | 128 ++++++++++++++++++++---------------
 1 file changed, 74 insertions(+), 54 deletions(-)

diff --git a/drivers/media/rc/sunxi-cir.c b/drivers/media/rc/sunxi-cir.c
index 48be400421cd..ccb9d6b4225d 100644
--- a/drivers/media/rc/sunxi-cir.c
+++ b/drivers/media/rc/sunxi-cir.c
@@ -169,10 +169,74 @@ static int sunxi_ir_set_timeout(struct rc_dev *rc_dev, unsigned int timeout)
 	return 0;
 }
 
+static int sunxi_ir_hw_init(struct device *dev)
+{
+	struct sunxi_ir *ir = dev_get_drvdata(dev);
+	u32 tmp;
+	int ret;
+
+	ret = reset_control_deassert(ir->rst);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(ir->apb_clk);
+	if (ret) {
+		dev_err(dev, "failed to enable apb clk\n");
+		goto exit_assert_reset;
+	}
+
+	ret = clk_prepare_enable(ir->clk);
+	if (ret) {
+		dev_err(dev, "failed to enable ir clk\n");
+		goto exit_disable_apb_clk;
+	}
+
+	/* Enable CIR Mode */
+	writel(REG_CTL_MD, ir->base + SUNXI_IR_CTL_REG);
+
+	/* Set noise threshold and idle threshold */
+	sunxi_ir_set_timeout(ir->rc, ir->rc->timeout);
+
+	/* Invert Input Signal */
+	writel(REG_RXCTL_RPPI, ir->base + SUNXI_IR_RXCTL_REG);
+
+	/* Clear All Rx Interrupt Status */
+	writel(REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
+
+	/*
+	 * Enable IRQ on overflow, packet end, FIFO available with trigger
+	 * level
+	 */
+	writel(REG_RXINT_ROI_EN | REG_RXINT_RPEI_EN |
+	       REG_RXINT_RAI_EN | REG_RXINT_RAL(ir->fifo_size / 2 - 1),
+	       ir->base + SUNXI_IR_RXINT_REG);
+
+	/* Enable IR Module */
+	tmp = readl(ir->base + SUNXI_IR_CTL_REG);
+	writel(tmp | REG_CTL_GEN | REG_CTL_RXEN, ir->base + SUNXI_IR_CTL_REG);
+
+	return 0;
+
+exit_disable_apb_clk:
+	clk_disable_unprepare(ir->apb_clk);
+exit_assert_reset:
+	reset_control_assert(ir->rst);
+
+	return ret;
+}
+
+static void sunxi_ir_hw_exit(struct device *dev)
+{
+	struct sunxi_ir *ir = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(ir->clk);
+	clk_disable_unprepare(ir->apb_clk);
+	reset_control_assert(ir->rst);
+}
+
 static int sunxi_ir_probe(struct platform_device *pdev)
 {
 	int ret = 0;
-	unsigned long tmp = 0;
 
 	struct device *dev = &pdev->dev;
 	struct device_node *dn = dev->of_node;
@@ -213,43 +277,26 @@ static int sunxi_ir_probe(struct platform_device *pdev)
 		ir->rst = devm_reset_control_get_exclusive(dev, NULL);
 		if (IS_ERR(ir->rst))
 			return PTR_ERR(ir->rst);
-		ret = reset_control_deassert(ir->rst);
-		if (ret)
-			return ret;
 	}
 
 	ret = clk_set_rate(ir->clk, b_clk_freq);
 	if (ret) {
 		dev_err(dev, "set ir base clock failed!\n");
-		goto exit_reset_assert;
+		return ret;
 	}
 	dev_dbg(dev, "set base clock frequency to %d Hz.\n", b_clk_freq);
 
-	if (clk_prepare_enable(ir->apb_clk)) {
-		dev_err(dev, "try to enable apb_ir_clk failed\n");
-		ret = -EINVAL;
-		goto exit_reset_assert;
-	}
-
-	if (clk_prepare_enable(ir->clk)) {
-		dev_err(dev, "try to enable ir_clk failed\n");
-		ret = -EINVAL;
-		goto exit_clkdisable_apb_clk;
-	}
-
 	/* IO */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	ir->base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(ir->base)) {
-		ret = PTR_ERR(ir->base);
-		goto exit_clkdisable_clk;
+		return PTR_ERR(ir->base);
 	}
 
 	ir->rc = rc_allocate_device(RC_DRIVER_IR_RAW);
 	if (!ir->rc) {
 		dev_err(dev, "failed to allocate device\n");
-		ret = -ENOMEM;
-		goto exit_clkdisable_clk;
+		return -ENOMEM;
 	}
 
 	ir->rc->priv = ir;
@@ -265,6 +312,7 @@ static int sunxi_ir_probe(struct platform_device *pdev)
 	ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
 	/* Frequency after IR internal divider with sample period in us */
 	ir->rc->rx_resolution = (USEC_PER_SEC / (b_clk_freq / 64));
+	ir->rc->timeout = IR_DEFAULT_TIMEOUT;
 	ir->rc->min_timeout = sunxi_ithr_to_usec(b_clk_freq, 0);
 	ir->rc->max_timeout = sunxi_ithr_to_usec(b_clk_freq, 255);
 	ir->rc->s_timeout = sunxi_ir_set_timeout;
@@ -291,41 +339,15 @@ static int sunxi_ir_probe(struct platform_device *pdev)
 		goto exit_free_dev;
 	}
 
-	/* Enable CIR Mode */
-	writel(REG_CTL_MD, ir->base+SUNXI_IR_CTL_REG);
-
-	/* Set noise threshold and idle threshold */
-	sunxi_ir_set_timeout(ir->rc, IR_DEFAULT_TIMEOUT);
-
-	/* Invert Input Signal */
-	writel(REG_RXCTL_RPPI, ir->base + SUNXI_IR_RXCTL_REG);
-
-	/* Clear All Rx Interrupt Status */
-	writel(REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
-
-	/*
-	 * Enable IRQ on overflow, packet end, FIFO available with trigger
-	 * level
-	 */
-	writel(REG_RXINT_ROI_EN | REG_RXINT_RPEI_EN |
-	       REG_RXINT_RAI_EN | REG_RXINT_RAL(ir->fifo_size / 2 - 1),
-	       ir->base + SUNXI_IR_RXINT_REG);
-
-	/* Enable IR Module */
-	tmp = readl(ir->base + SUNXI_IR_CTL_REG);
-	writel(tmp | REG_CTL_GEN | REG_CTL_RXEN, ir->base + SUNXI_IR_CTL_REG);
+	ret = sunxi_ir_hw_init(dev);
+	if (ret)
+		goto exit_free_dev;
 
 	dev_info(dev, "initialized sunXi IR driver\n");
 	return 0;
 
 exit_free_dev:
 	rc_free_device(ir->rc);
-exit_clkdisable_clk:
-	clk_disable_unprepare(ir->clk);
-exit_clkdisable_apb_clk:
-	clk_disable_unprepare(ir->apb_clk);
-exit_reset_assert:
-	reset_control_assert(ir->rst);
 
 	return ret;
 }
@@ -334,11 +356,9 @@ static int sunxi_ir_remove(struct platform_device *pdev)
 {
 	struct sunxi_ir *ir = platform_get_drvdata(pdev);
 
-	clk_disable_unprepare(ir->clk);
-	clk_disable_unprepare(ir->apb_clk);
-	reset_control_assert(ir->rst);
-
+	sunxi_ir_hw_exit(&pdev->dev);
 	rc_unregister_device(ir->rc);
+
 	return 0;
 }
 
-- 
2.26.2